Linear surgical stapler

ABSTRACT

A staple cartridge configured for use with a surgical stapler includes a cartridge body, a deck defined configured to compress tissue against an anvil of the surgical stapler, and a plurality of staple openings formed in the deck. A plurality of staples is disposed within the staple openings, with each staple having a pair of legs. A plurality of staple drivers is also disposed within the staple openings, with the staple drivers being actuatable to drive the staples through tissue and against the anvil to form the legs. Each of the staple drivers includes a driver body, a first pocket disposed on a first lateral side of the driver body, and a second pocket disposed on a second lateral side of the driver body. The first and second pockets are configured to receive the legs of the respective staple when the legs are formed against the anvil.

BACKGROUND

In some surgical operations, such as a gastrointestinal anastomosis, itmay be desirable to clamp down on one or more layers of tissue, cutthrough the clamped layers, and simultaneously drive staples through thelayers to substantially seal the severed layers of tissue together neartheir severed ends. One such instrument that may be used in suchoperations is a linear surgical stapler, also referred to as a “linearcutter.” A linear surgical stapler generally includes a first half(referred to as a “cartridge half” or “reload half”) having a distal jawconfigured to support a staple cartridge (or “reload”), and a secondhalf (referred to as an “anvil half”) having a distal jaw that supportsan anvil surface having staple forming features. The stapler furtherincludes a moveable clamp lever configured to releasably clamp thestapler halves together. The stapler halves are configured to pivotrelative to one another to receive and clamp tissue between the twodistal jaws when the clamp lever is closed. A firing assembly of thestapler is configured to be actuated to cut the clamped layers andsimultaneously drive staples through the tissue on either side of thecut line. After firing the stapler, the clamp lever may be opened, andthe stapler halves separated to release the severed and stapled tissue.

While various kinds of surgical stapling instruments and associatedcomponents have been made and used, it is believed that no one prior tothe inventor(s) has made or used the invention described in the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention,and, together with the general description of the invention given above,and the detailed description of the embodiments given below, serve toexplain the principles of the present invention.

FIG. 1 depicts a perspective view of an exemplary linear surgicalstapler, showing a cartridge half and an anvil half of the staplercoupled together with a clamp lever of the cartridge half in a fullyclosed position;

FIG. 2 depicts an exploded perspective view of the linear surgicalstapler of FIG. 1;

FIG. 3 depicts a perspective view of a proximal portion of the cartridgehalf of the linear surgical stapler of FIG. 1, showing a cartridgechannel in cross-section and the clamp lever in an open position toreveal internal features of the cartridge half;

FIG. 4 depicts a top perspective view of a firing assembly of the linearsurgical stapler of FIG. 1;

FIG. 5A depicts a side elevational view of the linear surgical staplerof FIG. 1, showing the stapler halves separated from one another;

FIG. 5B depicts a side elevational view of the linear surgical staplerof FIG. 1, showing proximal ends of the stapler halves coupled together;

FIG. 5C depicts a side elevational view of the linear surgical staplerof FIG. 1, showing a distal pin of the anvil half being received byclamp lever jaws of the cartridge half

FIG. 5D depicts a side elevational view of the linear surgical staplerof FIG. 1, showing closure of the clamp lever to fully clamp the staplerhalves together;

FIG. 5E depicts a side elevational view of the linear surgical staplerof FIG. 1, showing distal actuation of the firing assembly while thestapler halves are in the fully clamped state;

FIG. 6 shows a perspective view of an exemplary staple cartridgeconfigured for use with the linear surgical stapler of FIG. 1;

FIG. 7 depicts an exploded perspective view of the staple cartridge ofFIG. 6;

FIG. 8 depicts an enlarged perspective view of the staple cartridge ofFIG. 6, showing tissue gripping features disposed along a length of adeck surface of the staple cartridge;

FIG. 9 depicts a sectional end view of the staple cartridge of FIG. 6,taken along section line 9-9 in FIG. 6;

FIG. 10 depicts an enlarged top plan view of tissue gripping featuresdisposed on the deck surface of the staple cartridge of FIG. 6;

FIG. 11 depicts an enlarged perspective view of tissue gripping featuresdisposed at a distal end of the deck surface of the staple cartridge ofFIG. 6;

FIG. 12 depicts a perspective view of an exemplary pair of stapledrivers and respective staples of the staple cartridge of FIG. 6;

FIG. 13 depicts an enlarged perspective view of a top portion of thestaple drivers of FIG. 12;

FIG. 14 depicts a top plan view of the staple drivers of FIG. 12;

FIG. 15 depicts a side elevational view of a portion of the staplecartridge of FIG. 6 and a confronting portion of an anvil surface of theanvil half of the surgical stapler of FIG. 1, showing the staplerportions cooperating to form a pair of staples;

FIG. 16 depicts a top plan view of the pair of staples of FIG. 15 in aformed state;

FIG. 17 depicts a perspective view of another exemplary pair of stapledrivers configured for use with the staple cartridge of FIG. 6;

FIG. 18 depicts an enlarged perspective view of a top portion of thestaple drivers of FIG. 17;

FIG. 19 depicts a top plan view of the staple drivers of FIG. 17

FIG. 20 depicts an enlarged perspective view of one of the stapledrivers of FIG. 17 in combination with a staple formed by the stapledriver in cooperation with an anvil pocket of the anvil half of thelinear surgical stapler of FIG. 1;

FIG. 21 depicts a perspective view of an underside of a proximal portionof the firing assembly of FIG. 4, configured for use with the linearsurgical stapler of FIG. 1;

FIG. 22 depicts an enlarged cross-sectional perspective view of aportion of the cartridge half of the linear surgical stapler of FIG. 1,showing an exemplary guide block through which firing beams of thefiring assembly are configured to translate;

FIG. 23 depicts a perspective view of the guide block and a lockoutspring of the cartridge half of FIG. 22;

FIG. 24 depicts a perspective view of the lockout spring of FIG. 23;

FIG. 25 depicts a top plan view of the guide block, the lockout spring,and the firing beams of the configuration of FIG. 22;

FIG. 26 depicts a top plan view of another exemplary lockout spring incombination with the guide block and the firing beams of theconfiguration of FIG. 22;

FIG. 27A depicts an enlarged side cross-sectional view of the cartridgehalf of the linear surgical stapler of FIG. 1, showing a knife beam ofthe firing assembly in a raised lockout position relative to the guideblock prior to insertion of an unspent staple cartridge;

FIG. 27B depicts an enlarged side cross-sectional view of the cartridgehalf of the linear surgical stapler of FIG. 1, showing the knife beam ina lowered firing position relative to the guide block followinginsertion of an unspent staple cartridge, which is represented byschematic depiction of an extended swing tab thereof;

FIG. 27C depicts an enlarged side cross-sectional view of the cartridgehalf of the linear surgical stapler of FIG. 1, showing distal actuationof the firing assembly over the lockout spring;

FIG. 28 depicts an enlarged cross-sectional perspective view of aportion of the cartridge half of the linear surgical stapler of FIG. 1,showing an exemplary alternative guide block through which firing beamsof the firing assembly are configured to translate;

FIG. 29 depicts a perspective view of the guide block and the lockoutspring of the cartridge half of FIG. 28;

FIG. 30A depicts an enlarged side cross-sectional view of the cartridgehalf of FIG. 28, showing the knife beam of the firing assembly in araised lockout position relative to the guide block prior to insertionof an unspent staple cartridge;

FIG. 30B depicts an enlarged side cross-sectional view of the cartridgehalf of FIG. 28, showing the knife beam in a lowered firing positionrelative to the guide block following insertion of an unspent staplecartridge, which is represented by schematic depiction of an extendedswing tab thereof;

FIG. 30C depicts an enlarged side cross-sectional view of the cartridgehalf of FIG. 28, showing distal actuation of the firing assembly overthe lockout spring;

FIG. 31 depicts a side elevational view of the distal portion of anotherexemplary anvil half of a linear surgical stapler, showing a distal jawportion having concavely curved mounting surfaces and an anvil platehaving a similar concave curvature;

FIG. 32A depicts a cross-sectional end view of the distal jaw portion ofthe anvil half of FIG. 31, taken along section line 32A-32A in FIG. 31,with a distal tip structure being omitted;

FIG. 32B depicts a cross-sectional end view of the distal jaw portion ofthe anvil half of FIG. 31, taken along section line 32B-32B in FIG. 31;

FIG. 32C depicts a cross-sectional end view of the distal jaw portion ofthe anvil half of FIG. 31, taken along section line 32C-32C in FIG. 31;

FIG. 33A depicts a side elevational view of a distal portion of a linearsurgical stapler having the anvil half of FIG. 31 and the cartridge halfof FIG. 1, with shrouds of the stapler halves being omitted, showing thestapler halves in a partially clamped state in which the anvil plateexhibits a concavely curved configuration;

FIG. 33B depicts a side elevational view of the distal portion of thelinear surgical stapler of FIG. 33A, showing the stapler halves in afully clamped state in which the anvil plate assumes a straightconfiguration; and

FIG. 34 depicts a schematic side elevational view of another exemplarystaple cartridge and the distal portion of an anvil half of a linearsurgical stapler, showing the staple cartridge having staple drivers ofvarying heights.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the invention may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presentinvention, and together with the description serve to explain theprinciples of the invention; it being understood, however, that thisinvention is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the invention shouldnot be used to limit the scope of the present invention. Other examples,features, aspects, embodiments, and advantages of the invention willbecome apparent to those skilled in the art from the followingdescription, which is by way of illustration, one of the best modescontemplated for carrying out the invention. As will be realized, theinvention is capable of other different and obvious aspects, all withoutdeparting from the invention. Accordingly, the drawings and descriptionsshould be regarded as illustrative in nature and not restrictive.

For clarity of disclosure, the terms “proximal” and “distal” are definedherein relative to a surgeon, or other operator, grasping a surgicalinstrument having a distal surgical end effector. The term “proximal”refers to the position of an element arranged closer to the surgeon, andthe term “distal” refers to the position of an element arranged closerto the surgical end effector of the surgical instrument and further awayfrom the surgeon. Moreover, to the extent that spatial terms such as“upper,” “lower,” “vertical,” “horizontal,” or the like are used hereinwith reference to the drawings, it will be appreciated that such termsare used for exemplary description purposes only and are not intended tobe limiting or absolute. In that regard, it will be understood thatsurgical instruments such as those disclosed herein may be used in avariety of orientations and positions not limited to those shown anddescribed herein.

As used herein, the terms “about” and “approximately” for any numericalvalues or ranges indicate a suitable dimensional tolerance that allowsthe part or collection of components to function for its intendedpurpose as described herein.

I. Exemplary Linear Surgical Stapler

A. Overview of Linear Surgical Stapler

FIGS. 1-2 show an exemplary linear surgical stapler (10) (also referredto as a “linear cutter”) suitable for use in a variety of cutting andstapling procedures, such as a gastrointestinal anastomosis procedure.Linear surgical stapler (10) includes a cartridge half (12) (alsoreferred to as a “reload half”) and an anvil half (14) configured toreleasably couple together to clamp tissue therebetween for simultaneouscutting and stapling of the clamped tissue.

Cartridge half (12) includes an elongate cartridge channel (16) having aproximal frame portion (18) and a distal jaw portion (20). Proximalframe portion (18) slidably retains a firing assembly (100) and includesa laterally opposed pair of upright side flanges (22). Each side flange(22) includes a vertical slot (24) arranged at a distal end thereof, anda tapered notch (26) arranged at a proximal end thereof. An outwardlyprojecting stiffening rib (28) extends longitudinally between the distalslot (24) and proximal notch (26) of each side flange (22) and isconfigured to provide the side flange (22) with enhanced stiffness. Anoutwardly flared upper segment (30) defines an upper edge of a proximalportion of each side flange (22) and is configured to facilitate receiptof anvil half (14) by cartridge half (12). Each side flange (22) furtherincludes an elongate firing slot (32) extending longitudinally betweenproximal notch (26) and distal slot (24) along a lower side of sideflange (22). Elongate firing slots (32) are configured to guide firingassembly (100) between proximal and distal positions. Firing assembly(100) is described in greater detail below in connection with FIG. 4.Distal jaw portion (20) of cartridge channel (16) is configured toreceive a staple cartridge (130) (or “reload”), which is described ingreat detail below in connection with FIGS. 6-20.

Cartridge half (12) further includes a clamp lever (40) (also referredto as a “latch lever”) pivotably coupled to cartridge channel (16) witha clamp lever pivot pin (42), which is arranged in approximate alignmentwith distal slots (24) of cartridge channel side flanges (22). Clamplever (40) includes an elongate lever arm (44) having a free proximalend (46) and a distal end that is pivotably coupled to a lower portionof cartridge channel (16) with pivot pin (42). A pair of opposed jaws(48) extend distally from the distal end of lever arm (44) alongsidecartridge channel side flanges (22). Each jaw (48) includes a curvedslot (50) having a closed proximal end and an open distal end configuredto receive a latch pin (68) of anvil half (14), as described below.

Clamp lever (40) is operable to pivot relative to cartridge channel (16)between an open position in which proximal end (46) of lever arm (44) isspaced from cartridge channel frame portion (18), and a closed positionin which proximal end (46) confronts cartridge channel frame portion(18). Actuation of clamp lever (40) from the open position to the closedposition operates to capture the opposed lateral ends of latch pin (68)within clamp lever jaw slots (50), and thereby clamp anvil half (14)against cartridge half (12), as shown and described below in connectionwith FIGS. 5C-5D. In that regard, the curvature of each jaw slot (50)defines respective upper and lower camming surfaces configured to engageand draw the respective lateral end of latch pin (68) toward cartridgechannel (16) as clamp lever (40) is pivotably closed. A resilient membershown in the form of a flat spring (52) biases lever arm (44) toward theopen position. Accordingly, flat spring (52) promotes disengagement ofclamp lever jaws (48) from anvil half latch pin (68) upon initialadvancement of clamp lever (40) from the closed position toward the openposition. As best shown in FIGS. 2 and 3, clamp lever (40) furtherincludes a latch member (54) arranged at proximal end (46) of lever arm(44). Clamp lever latch member (54) is configured to resiliently andreleasably engage a proximal end of cartridge channel frame portion (18)and thereby releasably retain clamp lever (40) in the closed position,for instance while stapler (10) is being fired.

Anvil half (14) of linear surgical stapler (10) includes an elongateanvil channel (60) having a proximal frame portion (62) and a distal jawportion (64). Proximal frame portion (62) includes a laterally opposedpair of upright side flanges (66) that are configured to be receivedbetween cartridge channel side flanges (22) when anvil half (14) iscoupled with cartridge half (12). A distal latch projection in the formof latch pin (68) extends laterally through the distal ends of anvilchannel side flanges (66), and a proximal pivot projection in the formof a proximal pin (70) extends laterally through the proximal ends ofanvil channel side flanges (66). Anvil pins (68, 70) are configured tofacilitate coupling of anvil half (14) with cartridge half (12), asdescribed below.

Distal jaw portion (64) of anvil half (14) supports an anvil plate (72)that defines an anvil surface having a plurality of staple formingpockets (74) (see FIG. 15) configured to deform legs (174) of staples(170) ejected by staple cartridge (130) when stapler (10) is fired, forexample as described in greater detail below. In some versions, theanvil surface may be formed integrally with distal jaw portion (64).Distal jaw portion (64) of anvil half (14) additionally supports atapered distal tip member (76). In some versions, distal tip member (76)may be selectively extendable relative to distal jaw portion (64) inaccordance with the teachings of U.S. patent application Ser. No.16/165,587, entitled “Decoupling Mechanism for Linear Surgical Stapler,”filed on Oct. 19, 2018, the disclosure of which is incorporated byreference herein.

As shown in FIG. 2, linear surgical stapler (10) further includes aplurality of shrouds (56, 78) that cover select portions of stapler (10)and promote effective grip and manipulation of stapler (10) by anoperator during use. In the present example, a clamp lever shroud (56)is affixed to and covers an outwardly facing side of clamp lever (40)such that clamp lever shroud (56) is configured to pivot with clamplever (40) relative to cartridge channel (16). Additionally, an anvilshroud (78) is affixed to and covers an outwardly facing side of anvilchannel (60). In some versions, anvil shroud (78) may be coupled withanvil channel (60) in accordance with the teachings of U.S. patentapplication Ser. No. 16/102,170, entitled “Clamping Assembly for LinearSurgical Stapler,” filed on Aug. 13, 2018, the disclosure of which isincorporated by reference herein. It will be appreciated that in otherversions, shrouds (56, 78) may be coupled with clamp lever (40) andanvil channel (60) in a variety of other suitable manners readilyapparent to those of ordinary skill in the art.

As shown best in FIG. 3, a proximal end of cartridge half (12) includesa retaining assembly (80) configured to releasably retain portions ofanvil half (14) and firing assembly (100). Retaining assembly (80) ofthe present example includes an anvil latch member (82) and a detentmember (84), both of which are rotatably coupled with a proximal end ofcartridge channel (16) via a laterally extending pin (86) arrangedproximally of firing slots (32). A torsion spring (not shown) isconfigured to resiliently bias anvil latch member (82) and detent memberin opposite rotational directions about the lateral axis defined by pin(86).

Anvil latch member (82) includes an upper finger (88) configured toreleasably capture proximal anvil pin (70) when pin (70) is directedinto proximal tapered notches (26) of cartridge channel (16), therebycoupling the proximal ends of stapler halves (12, 14). A lower end ofanvil latch member (82) defines a release button (90) configured to bedepressed by the operator when clamp lever (40) is in the open positionto release proximal pin (70) from latch finger (88) and thereby permitseparation of the proximal ends of stapler halves (12, 14). Detentmember (84) includes a distal finger (88) configured to releasablycapture the proximal end of a slide block (102) of firing assembly (100)when firing assembly (100) us in a proximal home position, shown in FIG.3. Detent member (84) further includes a proximal hook (94) configuredto releasably capture an upper tip of clamp lever latch member (54)while slide block (102) is positioned distally of its proximal homeposition, thereby preventing actuation of clam lever latch member (54)and opening of clamp lever (40) during firing of stapler (10). Whenfiring assembly (100) is in its proximal home position (i.e., before orafter firing of stapler (10)), proximal hook (94) of detent member (84)permits clamp lever latch member (54) to rotatably disengage proximalframe portion (18) of cartridge channel (16) in response to actuation bythe operator. As a result, clamp lever (40) may then be opened.Retaining assembly (80) and related components of cartridge half (12)may be further configured and operable in accordance with at least someof the teachings of U.S. patent application Ser. No. 16/102,164,entitled “Firing System for Linear Surgical Stapler,” filed on Aug. 13,2018, the disclosure of which is incorporated by reference herein.

As shown best in FIG. 4, firing assembly (100) of cartridge half (12)includes slide block (102), a pair of actuators (104, 106) (or “firingknobs”) pivotably coupled to slide block (102), and a plurality ofelongate beams (108, 112) extending distally from slide block (102). Apair of side beams (108) are coupled at their proximal ends to a distalend of slide block (102) and terminate distally in a pair of cam ramps(110). Cam ramps (110) are configured to engage the undersides of stapledrivers (180) housed within staple cartridge (130) (see FIG. 7) andactuate staple drivers (180) upwardly to thereby drive (or “fire”)staples (170) from cartridge (130) into tissue clamped between staplecartridge (130) and anvil plate (72). A center beam (112) is coupledwith side beams (108) via a bridge member (114) (or “knife block”)spaced distally from slide block (102). Center beam (112) terminatesdistally in a distally angled knife member (116) having a distal cuttingedge (118) configured to cut tissue clamped between the distal portionsof stapler halves (12, 14). A distal portion of center beam (112)additionally includes an upwardly projecting stop element (120) proximalto knife member (116), and a distally facing lockout projection (122)proximal to stop element (120).

Each actuator (104, 106) of firing assembly (100) is configured androtatable relative to slide block (102) between a deployed position anda retracted position such that only one actuator (104, 106) may bedeployed at a time, for example as described in greater detail in U.S.patent application Ser. No. 16/102,164, incorporated by reference above.In the deployed position, an actuator (104, 106) may be driven distallyby an operator to actuate firing assembly (100) distally through stapler(10) and thereby simultaneously cut and staple tissue clamped betweenstapler halves (12, 14).

B. Exemplary Use of Linear Surgical Stapler

FIGS. 5A-5E show exemplary coupling of stapler halves (12, 14) andsubsequent firing of assembled stapler (10) during a surgical procedure.As shown in FIG. 5A, clamp lever (40) of cartridge half (12) is providedin the open position so that jaw slots (50) align with vertical slots(24) of cartridge channel side flanges (22). Additionally, firingassembly (100) is maintained in its proximal home position by detentmember (84) of retaining assembly (80), as shown in FIG. 3 describedabove. At this stage, a section of tissue (not shown) to be stapled andcut may be positioned over the top of staple cartridge (130) disposed indistal jaw portion (20) of cartridge half (12). Alternatively, thetissue may be positioned over staple cartridge (130) following couplingof the proximal ends of stapler halves (12, 14), described below.

As shown in FIG. 5A-5B, the proximal ends of stapler halves (12, 14) arealigned with one another and proximal anvil pin (70) is directeddownwardly into proximal tapered notches (26) of cartridge channel (16)to engage upper finger (88) of anvil latch member (82). This engagementforces anvil latch member (82) to resiliently rotate clockwise, thusenabling upper finger (88) of anvil latch member (82) to capture anvilpin (70) and thereby releasably couple together the proximal ends ofstapler halves (12, 14), as seen in FIG. 5B. As shown in FIG. 5C, andwith clamp lever (40) remaining in the open position, anvil half (14) isrotated toward anvil half (14) about proximal anvil pin (70) so thatdistal latch pin (68) of anvil half (14) is received into vertical slots(24) of cartridge channel side flanges (22) and jaw slots (50) of clamplever (40). Distal jaw portions (20, 64) of stapler halves (12, 14) arenow in a partially approximated state such that tissue receivedtherebetween may be finally adjusted before clamping.

As shown in FIG. 5D, clamp lever (40) is closed to draw anvil latch pin(68) against the closed proximal ends of jaw slots (50) and therebyfully clamp anvil half (14) against cartridge half (12), with tissue(not shown) clamped between staple cartridge (130) and anvil plate (72).A slight transverse gap is defined between staple cartridge (130) andanvil plate (72) by a tissue gap post (146) of staple cartridge (130)(see FIG. 6), thus accommodating the tissue therebetween with apredetermined degree of tissue compression. As shown in FIG. 6, tissuegap post (146) is disposed at a distal end of staple cartridge (130) andis configured to contact a distal end of anvil plate (72) when stapler(10) is in the fully clamped state shown in FIG. 5D.

As shown in FIG. 5E, upon reaching the fully clamped state, stapler (10)may be fired by driving a deployed actuator (104, 106) of firingassembly (100) distally along proximal frame portion (18) of cartridgehalf (12). As described above in connection with FIG. 4, this actioncauses elongate beams (108, 112) of firing assembly (100) to translatedistally through corresponding channels formed in staple cartridge (130)and thereby fire staples into the clamped tissue via cam ramps (110) andstaple drivers (180), and simultaneously cut the clamped tissue withknife member (116). Following completion of the firing stroke, firingassembly (100) is returned to its proximal home position via theactuator (104, 106). Clamp lever latch member (54) may then be depressedto release the proximal end of clamp lever (40) from cartridge channel(16), thus permitting clamp lever (40) to be re-opened. Then, releasebutton (90) of retaining assembly (80) may be depressed to release anvilhalf (14) from cartridge half (12) so that stapler halves (12, 14) maybe separated from one another, thereby releasing the newly stapled andsevered tissue. It will be understood that in some versions, stapler(10) may include features that promote decoupling of stapler halves (12,14) similar to those features disclosed in U.S. patent application Ser.No. 16/165,587, incorporated by reference above.

II. Exemplary Staple Cartridge Having Staple Drivers and Tissue GripFeatures that Promote Proper Formation of Three-Dimensional Staples

As described below in connection with FIGS. 15-16, staple cartridge(130) of linear surgical stapler (10) is configured to apply staples(170) having a three-dimensional (“3D”) formed configuration in whichlegs of each staple (170) are formed such that the leg tips arelaterally offset from one another, thus providing the formed staple(170) with a non-planar shape. Such a staple configurationadvantageously provides enhanced hemostasis and even distribution ofcompression forces along the resulting staple line applied to thepatient tissue. Additionally, staple cartridge (130) is provided withstand-off members (152, 160, 162, 164) to enhance the ability of staplecartridge (130) to effectively grip tissue clamped between staplecartridge (130) and anvil plate (72) during the stapling and cuttingsteps described above. Accordingly, it may be desirable to suitablyshape certain features of staple cartridge (130) to provide properclearances to promote proper 3D formation of staples (170) and avoidstaple malformation. Provision of such clearances also advantageouslyreduces the user input force required to actuate firing assembly (100)distally to fire staple cartridge (130).

It will be understood that while the features shown and described beloware presented in the context of staple cartridge (130) for linearsurgical stapler (10), such features may also be applied to staplecartridges configured for use with various other types of surgicalstaplers.

A. Overview of Exemplary Staple Cartridge

As shown in FIGS. 6 and 7, staple cartridge (130) includes an elongatecartridge body (132), and a plurality of staples (170) and stapledrivers (180) housed within cartridge body (132). A lockout bypassfeature in the form of a swing tab (144) is rotatably coupled to aproximal end of cartridge body (132) and is described in greater detailbelow. In some versions, staple cartridge (130) may further include abottom tray (not shown) that extends along an underside of cartridgebody (132) and facilitates retention of staples (170) and staple drivers(180) within cartridge body (132).

Referring briefly to FIG. 12, each staple (170) includes a central crown(172) and a pair of legs (174) extending away from crown (172) andhaving leg tips (176). In the unformed state of staple (170), crown(172) and legs (174) form a U-like shape in which the leg tips (176)extend away from crown (172), and crown (172) and legs (174) reside in acommon plane such that unformed staple (170) has a 2-dimensional shape.Referring briefly to FIGS. 15 and 16, in the 3D formed state of staple(170), each leg (174) has been bent by a respective staple formingpocket (74) of anvil plate (72) such that the leg tips (176) extendtoward crown (172). More specifically, as shown in FIG. 16, each formedleg tip (176) is laterally offset from one another and from crown (172)on opposed sides of crown (172), thus providing formed staple (170) witha 3-dimensional shape having the functional benefits described above.

Returning to FIGS. 6 and 7, cartridge body (132) of the present exampleextends linearly along a longitudinal axis between a proximal end havinga pair of hooks (134) and a distal end having a tapered nose (136).Proximal hooks (134) are configured to releasably capture clamp leverpivot pin (42) and extend downwardly through corresponding openingsformed in a floor of cartridge channel (16) when staple cartridge (130)is seated within distal jaw portion (20) of cartridge channel (16). Apair of wing tabs (138) disposed on the lateral sides of cartridge body(132) near the proximal end are configured to facilitate insertion andremoval of staple cartridge (130) relative to distal jaw portion (20).

As shown best in FIGS. 6-9, an upper side of cartridge body (132)defines a deck (140). An elongate knife slot (142) extendslongitudinally through deck (140) along the longitudinal axis of staplecartridge (130) and is configured to slidably receive knife member (116)of firing assembly (100) therethrough in response to distal actuationthereof, described above. A firing lockout bypass feature in the form ofa swing tab (144) is rotatably coupled to cartridge body (132) at aproximal end of knife slot (142). Swing tab (144) is configured torotate between a deployed position in which swing tab (144) extendsperpendicularly across the proximal end of knife slot (142), and aretracted position in which swing tab (144) extends parallel to knifeslot (142). As shown and described below in connection with FIGS.27A-27B, swing tab (144) in the deployed position is configured to urgefiring assembly (100) from a lockout state toward a firing state inwhich firing beams (108, 112) may translate distally through staplecartridge (130) to enact stapling and cutting of tissue clamped bystapler (10).

A rigid tissue gap post (146) is secured at a distal end of knife slot(142) and protrudes upwardly away from cartridge deck (140). A roundedupper end of tissue gap post (146) is configured to contact a distal endof anvil plate (72) and thereby define a tissue gap between cartridgedeck (140) and anvil plate (72) when stapler halves (12, 14) are clampedtogether in the manner described above.

A pair of elongate ribs (148) extend along opposing sides of knife slot(142) and elongate ribs (148), and project away from deck (140) todefine raised surfaces. Elongate ribs (148) terminate at proximal anddistal ends of knife slot (142) and are configured to promote enhancedgripping of tissue along knife slot (142), thus stabilizing the tissueduring cutting by knife member (116). As shown in FIG. 11, elongate ribs(148) of the present version have tapered distal ends disposed proximalto tissue gap post (146).

Cartridge body (132) of staple cartridge (130) further includes aplurality of staple openings (150) that extend transversely throughcartridge body (132) and open to deck (140). In the present example,staple openings (150) are arranged in first and second parallel rowsalong each side of knife slot (142), such that the staple openings (150)of each row are longitudinally staggered relative to staple openings(150) of the adjacent row. It will be understood that various suitablearrangements and quantities of staple openings (150) may be provided inother versions of staple cartridge (130). Each staple opening (150) isconfigured to house a respective staple driver (180) and staple (170)therein. As described above, cam ramps (110) of firing assembly areconfigured to engage the undersides of staple drivers (180) and actuatestaple drivers (180) upwardly within staple openings (150) to therebydrive (or “fire”) staples (170) from staple openings (150), into tissue,and against anvil plate (72).

As shown best in FIGS. 8-11, staple cartridge (130) further includes aplurality of tissue gripping members in form of stand-off members (152,160, 162, 164) that are arranged on and project upwardly from cartridgedeck (140). Stand-off members (152, 160, 162, 164) are distributed alonga length of deck (140) and are laterally offset from knife slot (142)and elongate ribs (148) to align with and open to a respective one ormore staple openings (150). As described below, stand-off members (152,160, 162, 164) are configured to grip and thereby stabilize tissue whendeck (140) and anvil plate (72) are clamped together; and, moreover,optimize tissue compression at the staple locations to facilitateeffective stapling and cutting of the tissue. While stand-off members(152, 160, 162, 164) are formed integrally with cartridge body (132) inthe present version, it will be understood that stand-off members (152,160, 162, 164) may be formed separately from and coupled to cartridgebody (132) in other versions.

As shown in FIGS. 8-10, a first group of stand-off members on cartridgedeck (140) is shown in the form of cleats (152) arranged discretelyalong the length of knife slot (142) in alignment with staple openings(150). Each cleat (152) includes a pair of end features (154) that facein opposing longitudinal directions. In particular, a first end feature(154) opens to and wraps partially around an end portion of a firststaple opening (150) within a given row of staple openings (150), and anopposed second end feature (154) opens to and wraps partially around anend portion of an adjacent second staple opening (150) within the samerow of staple openings (150). First and second end features (154) areintegrally connected by a recessed bridge feature (156).

Each end feature (154) of a cleat (152) has a generally U-shapedcross-section in a plane that extends parallel to deck (140), along theheight of cleat (152). Each end feature (154) also defines an inner wallthat joins with and protrudes outwardly from an inner wall of therespective staple opening (150). In this manner, each end feature (154)opens to and communicates with a respective staple opening (150).Accordingly, each end feature (154) is configured to guide a respectivestaple leg (174) of a corresponding staple (170) (see FIG. 12), as wellas the respective staple driver (180), as the staple (170) is ejectedupwardly from the staple opening (150) by the staple driver (180). Eachend feature (154) thus cooperates with a confronting end feature (154)of an adjacent cleat (152), or with an endcap (160) (see FIG. 11)described below, to provide such guidance of staples (170) and stapledrivers (180).

As shown best in FIGS. 8 and 10, each end feature (154) of a cleat (152)tapers toward the respective recessed bridge feature (156) along aheight of cleat (152) in a direction away from deck (140), thusproviding each cleat (152) with a trapezoidal-shaped side profile. Inthat regard, as shown best in FIG. 10, each end feature (154) includesan angled end surface (155) that slopes toward recessed bridge feature(156) and is rounded along a height thereof. This rounded configurationof angled end surfaces (155) enables each end feature (154) to confrontthe respective staple leg (174) and respective staple driver (180) tothereby effectively guide the staple (170) and staple driver (180)upwardly, while also providing effective clearance to promote proper 3Dformation of the staple leg (174). In particular, the roundedconfiguration of angled end surfaces (155) mitigates the risk of a tipof staple leg (174) striking an end feature (154) when the staple leg(174) is being formed by anvil plate (72), which might otherwise inducemalformation of the staple leg (174).

As shown in FIGS. 8 and 10, the laterally outermost rows of cleats (152)on cartridge deck (140) of the present example are formed with outersides having planar faces (158) that are angled relative to a length ofstaple cartridge (130). Accordingly, these particular cleats (152) areasymmetrical about their longitudinal axes, which may help to facilitatea molding process for forming cartridge body (132).

While cleats (152) of the present example are discretely formed relativeto one another such that each cleat (152) is freestanding and spacedapart from adjacent cleats (152), in other versions cleats (152) may beinterconnected with one another along one or more portions of cartridgedeck (140).

As shown in FIG. 11, cartridge deck (140) includes additional stand-offmembers in the form of proximally facing endcaps (160) disposed at thedistal ends of the rows of staple openings (150). In the presentversion, a proximal portion of each endcap (160) is similar in shape tocleat end features (154) described above. In particular, the proximalportion of each endcap (160) has a U-shape and wraps partially around adistal end portion of a respective staple opening (150). Accordingly,each endcap (160) cooperates with a confronting end feature (154) of anadjacent cleat (152) within the same row to guide a respective staple(170) and staple driver (180) during firing of staple cartridge (130).In the present example, each endcap (160) further includes a distal rampfeature (162) that tapers distally toward cartridge nose (136). Asimilar ramp feature (164) is positioned distally of and in longitudinalalignment with tissue gap post (146). Ramp features (162, 164) areconfigured to promote smooth insertion of the distal end of cartridgehalf (12) of stapler (10) into or underneath a tissue structure withoutthe tissue snagging on or otherwise bunching against cleats (152),endcaps (160), or tissue gap post (146).

In the present example, stand-off members (152, 160, 162, 164) protrudefrom cartridge deck (140) with a uniform maximum height and thuscollectively define a raised tissue engagement plane. In other versions,stand-off members (152, 160, 162, 164) may protrude from cartridge deck(140) with varying heights and thus define two or more raised tissueengagement planes.

FIGS. 12-14 show details of an exemplary pair of staple drivers (180) ofstaple cartridge (130). In the present example, each pair of stapledrivers (180) is integrally formed as a driver unit (181) having abridge element (182) that interconnects staple drivers (180) at theirlower ends (186). Staple drivers (180) of driver unit (181) are arrangedin a staggered formation in which staple drivers (180) are laterally andlongitudinally offset from one another, relative to the longitudinalaxis of staple cartridge (130), such that staple drivers (180) areconfigured to align with respective staple openings (150) of cartridgebody (132). As shown in FIG. 12, each staple driver (180) includes anupper end (184), a lower end (186), a first lateral side (188), and anopposed second lateral side (190). As seen in FIG. 14, staple driver(180) of the present example is formed along its height with atransverse cross-section having an elongate octagonal shape that definesfirst and second lateral sides (188, 190). Upper end (184) of stapledriver (180) includes a groove (192) configured to receive and supportthe crown (172) of a respective staple (170).

Each staple driver (180) of the present example is formed with pockets(194 a, 194 b) that open to upper end (184) and are configured toreceive staple leg tips (176) during formation of staple legs (174) byanvil plate (72) when stapler (10) is fired. In particular, firstlateral side (188) of driver (180) includes a first pair of adjacentpocket (194 a) at upper end (184), and second lateral side (190)includes a second pair of adjacent pockets (194 b) at upper end (184).In the present version, pockets (194 a, 194 b) are shaped uniformly andare arranged symmetrically such that each pocket (194 a) of firstlateral side (188) is aligned with an opposed pocket (194 b) of secondlateral side (190).

Each pocket (194 a, 194 b) of a staple driver (180) is defined by arespective chamfered surface (196) at upper end (184) and is separatedfrom the adjacent pocket (194 a, 194 b) of the same lateral side (188,190) by a boss (198) that is centrally positioned on the respectivelateral side (188, 190). Each chamfered surface (196) is angled towardgroove (192) such that pockets (194 a, 194 b) of first lateral side(188) and pockets (194 a, 194 b) of second lateral side (190) are angledtoward one another at their upper ends. Each pocket (194 a, 194 b)tapers in width in a direction toward lower end (186), so as to have agenerally trapezoidal shape. In contrast, each boss (198) tapers inwidth in a direction toward upper end (184), so as to have a generallytriangular shape. Moreover, each boss (198) defines an inner sidewall ofeach corresponding pockets (194 a, 194 b) near a center of upper groove(192), whereas each pocket (194 a, 194 b) is open at an opposed sidenear a corresponding end of upper groove (192). Bosses (198) areconfigured to facilitate proper seating of a staple crown (172) withinupper groove (192) during assembly of staple cartridge (130).

As shown in FIG. 15, each pocket (194 a, 194 b) of a staple driver (180)is configured to receive a staple leg tip (176) during formation ofstaples (170), such that each staple leg tip (176) confronts, thoughdoes not necessarily contact, a respective chamfered surface (196) ofstaple driver (180). Accordingly, and advantageously, provision ofpockets (194 a, 194 b) in staple drivers (180), along with roundedangled end surfaces (155) of cleats (152) described above, enablesproper 3D formation of staples (170) without staple legs (174) strikinglateral sides of staple drivers (180), or end features (154) of cleats(152), in manners that might otherwise induce malformation of staples(170).

As shown in FIG. 15, a first leg tip (176) of a staple (170) is receivedwithin a pocket (194 a) of first lateral side (188) of driver (180)during 3D staple formation. Similarly, a second leg tip (176) isreceived within a pocket (194 b) of second lateral side (190) that isdiagonally opposed from the first pocket (194 a). Accordingly, theremaining pocket (194 a) of first lateral side (188) and the diagonallyopposed remaining pocket (194 b) of second lateral side (190) are leftunused in the present example. However, it will be understood thatproviding a pair of pockets (194 a, 194 b) on each lateral side (188,190) of staple driver (180) enables staple drivers (180) to accommodatealternative configurations of staple forming pockets (74) of anvil plate(72) and resulting 3D formed configurations of staples (170). Forinstance, in some versions, at least some of the staple forming pockets(74) of anvil plate (72) may be alternatively configured to directstaple legs (174) into the unused pair of diagonally opposed pockets(194 a, 194 b) shown in FIG. 15. Accordingly, each staple driver (180)is thus configured to accommodate formation of a staple (170) having a3D configuration that is mirrored relative to the 3D configuration shownin FIG. 16.

B. Exemplary Alternative Staple Driver of Staple Cartridge

It may be desirable to alternatively configure staple cartridge (130) insome applications to accommodate different thicknesses of patient tissueto be fired upon. For instance, cartridge deck (140) and stand-offmembers (152, 160, 162, 164) may be alternatively configured indimension to accommodate stapling relatively thinner tissues, such asthose of vascular structures, for example. In such alternative versionsof staple cartridge (130), staples (170) may assume a slightly different3D formed shape relative to the staple shape shown in FIG. 16. Forinstance, the staple legs (174) may be formed such that the formedstaple (170) has a smaller formed height (e.g., approximately 0.035inches to 0.040 inches), and such that leg tips (176) are positionedcloser to a center of crown (172) than to the ends of crown (172), asshown in FIG. 20. Accordingly, pockets (194 a, 194 b) and bosses (198)of staple drivers (180) may warrant slight reconfiguring to accommodatesuch 3D formation differences of staples (170) without undesirablestriking of staple legs (174) on features of staple drivers (180), whichmight otherwise yield staple malformation and resulting increases inuser input force required to fire surgical stapler (10). Such anexemplary variation of staple drivers (180) is described in greaterdetail below.

FIGS. 17-19 show an exemplary alternative pair of staple drivers (200)configured for use with staple cartridge (130). Staple drivers (200) aresimilar to staple drivers (180) described above except as otherwisedescribed below. Similar to staple drivers (180), staple drivers (200)are integrally formed as a driver unit (201) having a bridge element(202) that interconnects staple drivers (200) at their lower ends (206)such that staple drivers (200) are arranged in a staggeredconfiguration. Additionally, each staple driver (200) includes an upperend (204), a lower end (204), a first lateral side (208), an opposedsecond lateral side (210), a groove (212) at upper end (204), and anelongate octagonal shape transversely along its height.

Unlike staple drivers (180), each lateral side (208, 210) of stapledriver (200) includes a single pocket (194) configured to receive astaple leg (174) during formation of staples (170). Each pocket (194) iscentrally positioned relative to upper groove (212) and is defined by arespective chamfered surface (216) that is angled toward groove (212) atits upper end. Each chamfered surface (216) is bound on its two sides bya pair of bosses (218), with each boss (218) being offset equidistantlyfrom a center of upper groove (212) along the span of groove (212). Eachboss (218) defines a respective sidewall of the corresponding pocket(194), and bosses (218) are shaped to provide each chamfered surface(216) with a generally rectangular shape. Additionally, each boss (218)has chamfered side surfaces so as to be tapered along its height in adirection toward upper end (204). Each lateral side (208, 210) of stapledriver (200) further includes a pair of side relief cuts definingtriangular surfaces (220) that abut the outer sides of bosses (218) andare coplanar with the respective chamfered surface (216).

As shown in FIG. 20, each pocket (194) is configured to receive arespective leg tip (176) of a staple (170) during 3D formation thereofby staple forming pockets (74) of anvil plate (72). Similar to pockets(194 a, 194 b) of staple drivers (180), pockets (214) pockets (214) ofstaple driver (200) are configured to receive staple leg tips (176) suchthat leg tips (176) confront, but do not necessarily contact, chamferedsurfaces (216). Accordingly, staple drivers (200) are thus configured topromote proper 3D formation of staples (170) in tissue, such asrelatively thinner tissues for which a formed staple height ofapproximately 0.035 inches to 0.040 inches, for example, is desired.

III. Exemplary Features for Minimizing Plastic Deformation of FiringLockout Spring of Linear Surgical Stapler

As described above, firing assembly (100) of linear surgical stapler(10) is translatable distally within cartridge channel (16) from aproximal home position (see FIG. 5D) to a distal fired position (seeFIG. 5E) to simultaneously staple and cut tissue clamped between thedistal portions of stapler halves (12, 14). As described in greaterdetail below, cartridge half (12) further includes a resilient lockoutmember (250) in the form of a leaf spring configured to bias firingassembly (100) toward a lockout state in the absence of an unfired (or“unspent”) staple cartridge (130) within distal jaw portion (20) ofcartridge half (12). When an unspent staple cartridge (130) is seatedwithin cartridge half (12), lockout spring (250) is deflected downwardlyby a deployed swing tab (144) of staple cartridge (130) to therebytransition firing assembly (100) to a firing state. In the firing state,firing assembly (100) is freely actuatable distally, over lockout spring(250) in a deflected state, to thereby fire stapler (10). After firingis complete, firing assembly (100) is retracted proximally to its homeposition, thus enabling lockout spring (250) to resume its originalstate and bias firing assembly (100) into a lockout state until thespent staple cartridge (130) is replaced with an unspent staplecartridge (130).

When actuated distally during a firing stroke, firing assembly (100)depresses lockout spring (250) toward a floor of cartridge channel (16).In some instances, this depression can result in plastic deformation oflockout spring (250), which could undesirably inhibit the ability oflockout spring (250) to operate effectively during subsequent firings ofstapler (10). Accordingly, it may be desirable to provide cartridge half(12) of stapler (10) with features that minimize the risk of suchplastic deformation.

As shown in FIG. 21, an underside of slide block (102) of firingassembly (100) includes a first recess (124) that opens to a distal endof slide block (102) and extends proximally. Additionally, an undersideof bridge element (114) includes a second recess (126) that extendsthrough a full axial thickness of bridge element (114). As describedbelow, these underside recesses (124, 126) are configured to receive aportion of lockout spring (250) when firing assembly (100) is actuateddistally to a fully fired state, and thereby aid in reducing the amountby which lockout spring (250) is forced to deflect during a firingstroke.

A. Exemplary Firing Lockout System of Linear Surgical Stapler

As shown in FIG. 22-24, cartridge half (12) of linear surgical stapler(10) comprises a firing lockout system that includes a guide block (230)(also referred to as a “spacer block”) and lockout spring (250). Guideblock (230) is secured to a floor (34) of cartridge channel (16) inapproximate alignment with distal slots (24) via clamp lever pivot pin(42), which extends laterally through openings formed in guide block(230).

As shown in FIG. 23, guide block includes a proximal body portion (232)having a first lateral width, and a distal body portion (234) having anarrowed second width. A center slot (236) extends longitudinallythrough proximal and distal body portions (232, 234) along a centerlineof guide block (230) and is configured to slidably receive center beam(112) of firing assembly (100) therethrough. A distal portion of centerslot (236) opens through an upper side of distal body portion (234) andis configured to slidably receive knife member (116), as shown in FIG.22. A pair of side slots (238) extend longitudinally through proximalbody portion (232) along either side of center slot (236) and areconfigured to slidably receive side beams (108) of firing assembly (100)therethrough. As shown best in FIGS. 23 and 27A-27C, proximal bodyportion (232) further includes a lower channel (240) that extendslongitudinally along a bottom end of center slot (236). As described ingreater detail below, lower channel (240) is sized with a transversedimension suitable to permit upward deflection of a base arm (252) oflockout spring (250) within lower channel (240) during firing of stapler(10). Distal body portion (234) includes a laterally opposed pair ofrecesses (242) configured to receive and retain a pair of distal anchorclips (258) of lockout spring (250).

As shown best in FIG. 23, lockout spring (250) is shown in the form ofan elongate leaf spring having a flat base arm (252) and a spring leg(254) extending proximally from base arm (252) at an upward angle andhaving a downwardly curved tip (256). A pair of anchor clips (258)extend upwardly from a distal end of base arm (252). As shown in FIGS.23 and 27A-27C, anchor clips (258) clasp against distal body portion(234) within distal recesses (242), and base arm (252) extendsproximally along an underside of distal body portion (234), over clamplever pivot pin (42), and through lower channel (240) of proximal bodyportion (232). Angled spring leg (254) extends proximally from lowerchannel (240) in longitudinal alignment with center slot (236).

As shown in FIGS. 25 and 27A-27C, center beam (112) of firing assembly(100) is positioned longitudinally over spring leg (254) of lockoutspring (250) such that center beam (112) is configured to translate overand in direct contact with spring leg (254). FIG. 26 shows an exemplaryalternative lockout spring (260) that is similar to lockout spring (250)except that lockout spring (260) includes a downwardly curved proximaltip (266) that is wider than at least medial and distal portions ofspring leg (264). Widened tip (266) is configured to maintain centerbeam (112) in engagement with spring leg (264) throughout longitudinalactuations of firing assembly (100).

As shown in FIG. 27A, in the absence of an unspent staple cartridge(130) from cartridge channel (16), spring leg (254) resiliently biasescenter beam (112) upwardly such that lockout projection (122) of centerbeam (112) engages a proximal face (233) of guide block (230). Thisengagement locks center beam (112) longitudinally relative to guideblock (230) and thus inhibits distal translation of firing assembly(100). FIG. 27B shows center beam (112) being pivoted downwardly towardcartridge channel floor (34) upon seating of an unspent staple cartridge(130) within cartridge channel (16). It will be understood that unspentstaple cartridge (130) is represented in FIGS. 27B and 30B by theschematic depiction of swing tab (144) in the deployed position. Asdescribed above, swing tab (144) in the deployed position extendstransversely across knife slot (142) of staple cartridge (130).Accordingly, seating of unspent staple cartridge (130) within cartridgechannel (16) causes swing tab (144) to engage the upper surface ofcenter beam (112), between knife member (116) and stop element (120),and drive center beam (112) downwardly to provide firing assembly (100)in a firing state. Seating of unspent staple cartridge (130) withincartridge channel (16) thus compresses spring leg (254) of lockoutspring (250) downwardly toward cartridge floor (34).

As shown in FIG. 27C, firing assembly (100) in the firing state is thendriven distally by an actuator (104, 106) of slide block (102) (see FIG.4). This forces firing beams (108, 112) to translate distally throughguide block (230) and into staple cartridge (130), thus actuating stapledrivers (180) upwardly to drive staples (170) into tissue andsimultaneously cutting the tissue with knife member (116). As firingassembly (100) advances distally toward the fully fired position shownin FIG. 27C, over spring leg (254), spring leg (254) is received throughunderside recess (126) of bridge element (114) and into underside recess(124) of slide block (102). Additionally, spring arm tip (256) isreceived into an opening (36) formed in cartridge channel floor (34).Simultaneously, base arm (252) of lockout spring (250) is permitted toresiliently deflect upwardly within lower channel (240) of guide block(230), which is also enabled by the ability of spring leg (254) to slidelongitudinally as needed within underside recesses (124, 126) of firingassembly (100). In this manner, lockout spring (250) is enabled toassume a deflected state that minimizes plastic deformation thereof inthe fully fired state of firing assembly (100).

B. Exemplary Alternative Firing Lockout System

In some instances, it may be desirable to alternatively configure guideblock (230) described above in other manners suitable to mitigateplastic deformation of lockout spring (250) when linear surgical stapler(10) is fired. FIGS. 28-30C show cartridge half (12) fitted with anexemplary alternative guide block (270) (or “spacer block”) that issimilar to guide block (230) described above except as otherwisedescribed below. In that regard, it will be understood that guide block(270) may be substituted for guide block (230) to cooperate with lockoutspring (250) and other components of cartridge half (12) described aboveto define a firing lockout system of linear surgical stapler (10).

Guide block (270) is secured to cartridge channel floor (34) andincludes a proximal body portion (272) having a first lateral width anda distal body portion (274) having a narrowed second width, a centerslot (276) extending longitudinally through proximal and distal bodyportions (272, 274), and a pair of side slots (278) extendinglongitudinally through proximal body portion (272) along either side ofcenter slot (276). Proximal body portion (272) further includes a lowerchannel (280) that extends longitudinally along a bottom end of centerslot (276). Distal body portion (274) includes a laterally opposed pairof recesses (282) configured to receive and retain distal anchor clips(258) of lockout spring (250).

As shown in FIG. 30A, proximal body portion (272) includes a pair ofspring support elements (284) projecting laterally inwardly from opposedwalls of lower channel (280), proximal to clamp lever pivot pin (42).Base arm (252) of lockout spring (250) extends longitudinally throughlower channel (240) such that base arm (252) is in contact with andsupported vertically by clamp lever pivot pin (42) and spring supportelements (284).

An elongate proximal member (286) is integrally joined with proximalbody portion (272) of guide block (270) and extends proximally alongcartridge channel floor (34) within proximal frame portion (18) ofcartridge channel (16). An upper surface of elongate proximal member(286) includes an elongate recess (288) that communicates with lowerchannel (280) and is configured to receive spring leg (254) of lockoutspring (250) therein when spring leg (254) is deflected downwardlyduring firing of stapler (10). A proximal end of elongate proximalmember (286) may include a user gripping feature (not shown) thatprojects downwardly through an opening in cartridge channel floor (34).Such a user gripping feature may be configured to serve as a bracingpoint for the finger of a user so the user may use a corresponding thumbof the same hand to depress release button (90) of retaining assembly(80) distally, described above.

An elongate distal member (290) is integrally joined with distal bodyportion (274) of guide block (270) and extends distally along cartridgechannel floor (34) within distal jaw portion (20) of cartridge channel(16). A distal end of elongate distal member (290) may include amechanical grounding feature (not shown) configured to fix elongatedistal member (290) axially relative to distal jaw portion (20) ofcartridge channel (16). As shown in FIGS. 30A-30C described below,firing assembly (100) is configured to translate over elongate proximaland distal members (286, 290) and through guide block (270).

As shown in FIG. 30A, in the absence of an unspent staple cartridge(130) from cartridge channel (16), spring leg (254) resiliently biasescenter beam (112) upwardly such that lockout projection (122) of centerbeam (112) engages a proximal face (273) of proximal body portion (272)of guide block (270). This engagement places firing assembly (100) in alockout state similar to that described above in connection with FIGS.27A-27C. FIG. 30B shows center beam (112) being pivoted downwardlytoward elongate proximal member (286) by the deployed swing tab (144) ofan unspent staple cartridge (130) upon seating of the unspent cartridge(130) within cartridge channel (16), thus placing firing assembly (100)in the firing state. Seating of unspent staple cartridge (130) alsocompresses spring leg (254) of lockout spring (250) downwardly towardelongate proximal member (286).

As shown in FIG. 30C, firing assembly (100) in the firing state is thendriven distally, thus forcing firing beams (108, 112) to translatedistally through guide block (270) and into staple cartridge (130), thusactuating staple drivers (180) upwardly to drive staples (170) intotissue and simultaneously cutting the tissue with knife member (116). Asfiring assembly (100) advances distally toward the fully fired positionshown in FIG. 30C, over spring leg (254), spring leg (254) is receivedthrough underside recess (126) of bridge element (114) and intounderside recess (124) of slide block (102) in a manner similar to thatdescribed above in connection with FIGS. 27A-27C. Additionally, springleg (254) and its proximal tip (256) are received into elongate recess(288) of elongate proximal member (286). Simultaneously, as shown inFIG. 30, a medial portion of base arm (252) of lockout spring (250) issupported vertically by one or both of clamp lever pivot pin (42) andspring support elements (284), while a proximal portion of base arm(252) is permitted to resiliently deflect within lower channel (280) ofguide block (270). In this manner, lockout spring (250) is enabled toassume a deflected state that minimizes plastic deformation thereof inthe fully fired state of firing assembly (100).

IV. Exemplary Features to Promote Uniform Height of Formed Staples

In some instances, clamping of anvil half (14) of linear surgicalstapler (10) against cartridge half (12) via closure of clamp lever (40)may result in distal jaw portion (64) of anvil channel (60) deformingalong its length relative to cartridge half (12). More specifically,such deformation results in anvil plate (72) and corresponding sidewallmount surfaces of distal jaw portion (64) assuming a convex curvaturerelative to staple cartridge deck (140) of cartridge half (12), forexample as shown in FIG. 34, which depicts an exaggerated curvature ofdistal jaw portion (64) for illustrative purposes. As a result, thelongitudinally extending tissue gap formed between staple cartridge deck(140) and anvil plate (72) may be inconsistent in size along a length ofstaple cartridge (130) and anvil plate (72). In particular, the tissuegap may be smaller at a medial location of staple cartridge (130) andanvil plate (72), and larger at proximal and distal end locations ofstaple cartridge (130) and anvil plate (72); for example as shown inFIG. 34. This inconsistency in tissue gap size can yield inconsistentheights of staples (170) formed in the clamped tissue, which isundesirable. Accordingly, it may be desirable to equip anvil half (14)and/or cartridge half (12) with features that account for suchdeflection of anvil channel (60) and ensure consistency in the formedheight of staples (170) along a length of staple cartridge (130) andanvil plate (72).

A. Exemplary Anvil Half Having Curved Anvil Plate

FIGS. 31-33B show an exemplary alternative anvil half (300) that issimilar to anvil half (14) described above except as otherwise describedbelow. As shown in FIG. 31, anvil half (300) includes an anvil channel(302) having a distal jaw portion (304) with a pair of sidewalls thatdefine a pair of concavely curved mount surfaces (306) to which an anvilplate (308) is mounted. Anvil plate (308) itself conforms to theconcavely curved mount surfaces (306) of anvil channel (302), such thatmount surfaces (306) and anvil plate (308) extend longitudinally alongthe same concavely curved path.

In some versions, anvil plate (308) may be initially formed with astraight, flat configuration and then deformed into a curvedconfiguration when being compressed against and secured to curved mountsurfaces (306) of anvil channel (302) (e.g., by welding) duringmanufacture of anvil half (302). In other versions, anvil plate (308)may be pre-formed with the same concave curvature as curved mountedsurfaces (306) prior to being secured to mount surfaces (306). In eithercase, the concave curvature of curved mount surfaces (306), and thus ofanvil plate (308), is selected as the inverse of the expected convexcurvature that distal jaw portion (304) assumes relative to staplecartridge deck (140) of cartridge half (12) when stapler halves (12,300) are fully clamped together.

As shown in FIG. 31, the concave curvature of mount surfaces (306) andanvil plate (308) in the present version is non-uniform along a lengthof distal jaw portion (304). Accordingly, a transverse height defined bydistal jaw portion (304) in combination with anvil plate (308) variesnon-uniformly along the length of distal jaw portion (304). Inparticular, as shown FIGS. 32A-32C, anvil half (302) exhibits a minimumtransverse height (H1) at a medial location of distal jaw portion (304);a maximum transverse height (H2) at a distal end of distal jaw portion(304); and an intermediate transverse height (H3) at a proximal end ofdistal jaw portion (304). In some other versions, the distal andproximal transverse heights (H2, H3) may be equal.

FIG. 33A shows anvil half (302) in a partially clamped state relative tocartridge half (12) described above. In this state, the distal end ofanvil plate (308) begins to clamp against tissue gap post (146) ofcartridge half (12). Meanwhile, mount surfaces (306) and anvil plate(308) of anvil half (300) still exhibit a concavely curved configurationrelative to deck (140) of staple cartridge (130). As shown in FIG. 33B,closing clamp lever (40) to its fully closed position forces distal jawportion (304) of anvil channel (302) to slightly deform along its lengthdistally of a latch pin (307). This deformation results in a flatteningof mount surfaces (306) and anvil plate (308) of anvil half (302), whilesimultaneously producing a concave curvature in an upper surface (309)of distal jaw portion (304). Consequently, anvil plate (308) extendsparallel to cartridge deck (140) and thus defines a tissue gap (G)therebetween that is uniform along the length thereof. This uniformtissue gap (G) promotes formation of staples (170) having uniformheights along the length of anvil plate (308) and cartridge deck (140).

B. Exemplary Staple Cartridge Having Staple Drivers of Varying Height

FIG. 34 schematically shows anvil channel (60) in a fully clamped staterelative to an exemplary alternative staple cartridge (310). Staplecartridge (310) is similar to staple cartridge (130) described aboveexcept that staple cartridge (310) includes a plurality of stapledrivers (312 a, 312 b, 312 c) that vary in height (H1, H2, H3) along alength of staple cartridge (310). In particular, in the present version,a medial portion of staple cartridge (310) includes staple drivers (312a) of a minimum height (H1); a distal end of staple cartridge (310)includes staple drivers (312 b) of a maximum height (H2); and a proximalend of staple cartridge (310) includes staple drivers (312 c) of anintermediate height (H3). In some other versions, the heights (H2, H3)of distal and proximal staple drivers (312 b, 312 c) may be equal.Though not shown, it will be understood that the heights of stapledrivers positioned between distal drivers (312 b) and medial drivers(312 a) may transition progressively from distal driver height (H2) tomedial driver height (H1). Similarly, the heights of staple driverspositioned between medial drivers (312 a) and proximal drivers (312 c)may transition progressively from medial driver height (H1) to proximaldriver height (H3).

As shown in FIG. 34 and as described above, distal jaw portion (64) ofanvil channel (60) flexes convexly toward staple cartridge (310) whenclamped against cartridge half (12). As a result, distal jaw portion(64) of anvil channel (60) assumes a curved state that yields a varyingtissue gap between anvil plate (72) and staple cartridge (310) along alength thereof. In particular, a medial section of anvil plate (72)defines a minimum tissue gap (G1); a distal end of anvil plate (72)defines a maximum tissue gap (G2); and a proximal end of anvil plate(72) defines an intermediate tissue gap (G3). The provision of stapledrivers (312 a, 312 b, 312 c) of varying heights (H1, H2, H3) correctsfor this variation in tissue gap (G1, G2, G3) by driving staples (170)shorter distances at the medial portion of cartridge (310) andprogressively larger distances in directions advancing proximally anddistally. As a result, staples (170) are formed with a uniform heightalong a full length of staple cartridge (310) despite the curvature ofanvil channel (60) and non-uniformity in tissue gaps (G1, G2, G3).

V. Exemplary Combinations

The following examples relate to various non-exhaustive ways in whichthe teachings herein may be combined or applied. It should be understoodthat the following examples are not intended to restrict the coverage ofany claims that may be presented at any time in this application or insubsequent filings of this application. No disclaimer is intended. Thefollowing examples are being provided for nothing more than merelyillustrative purposes. It is contemplated that the various teachingsherein may be arranged and applied in numerous other ways. It is alsocontemplated that some variations may omit certain features referred toin the below examples. Therefore, none of the aspects or featuresreferred to below should be deemed critical unless otherwise explicitlyindicated as such at a later date by the inventors or by a successor ininterest to the inventors. If any claims are presented in thisapplication or in subsequent filings related to this application thatinclude additional features beyond those referred to below, thoseadditional features shall not be presumed to have been added for anyreason relating to patentability.

Example 1

A staple cartridge configured for use with a surgical stapler,comprising: (a) a cartridge body; (b) a deck defined by the cartridgebody, wherein the deck is configured to compress tissue against an anvilof the surgical stapler; (c) a plurality of staple openings formed inthe deck; (d) a plurality of staples disposed within the stapleopenings, wherein each of the staples includes a pair of legs; and (e) aplurality of staple drivers disposed within the staple openings, whereinthe staple drivers are actuatable to drive the staples through tissueand against the anvil to form the legs, wherein each of the stapledrivers includes: (i) a driver body, (ii) a first pocket disposed on afirst lateral side of the driver body, and (iii) a second pocketdisposed on a second lateral side of the driver body, wherein the firstand second pockets are configured to receive the legs of the respectivestaple when the legs are formed against the anvil.

Example 2

The staple cartridge of Example 1, wherein the first pocket and thesecond pocket open to an upper end of the driver body.

Example 3

The staple cartridge of any of the preceding Examples, wherein each ofthe staple drivers further includes a first boss disposed on the firstlateral side of the driver body and a second boss disposed on the secondlateral side of the driver body, wherein the first boss defines asidewall of the first pocket, wherein the second boss defines a sidewallof the second pocket.

Example 4

The staple cartridge of any of the preceding Examples, wherein the firstpocket is defined by a first chamfered surface on the first lateral sideof the driver body, wherein the second pocket is defined by a secondchamfered surface on the second lateral side of the body.

Example 5

The staple cartridge of Example 4, wherein upper portions of the firstand second chamfered surfaces are angled toward one another.

Example 6

The staple cartridge of any of the preceding Examples, furthercomprising a plurality of stand-off members disposed on the deck,wherein the stand-off members project away from the deck and areconfigured to engage tissue.

Example 7

The staple cartridge of any of Example 6, wherein each of at least someof the stand-off members includes an end portion that wraps around aportion of an adjacent staple opening.

Example 8

The staple cartridge of Example 7, wherein the end portion includes arounded end surface configured to confront a respective one of thestaple drivers when the staple driver is actuated.

Example 9

The staple cartridge of any of Examples 6 through 8, wherein thestand-off members include a ramp feature disposed at a distal end of thedeck.

Example 10

The staple cartridge of Example 9, further comprising a post disposed ata distal end of the deck, wherein the ramp feature is arranged distallyof and in longitudinal alignment with the post along a longitudinal axisof the staple cartridge.

Example 11

The staple cartridge of any of the preceding Examples, furthercomprising: (a) an elongate slot formed in the deck, wherein theelongate slot is configured to slidably receive a cutting membertherethrough, wherein the staple openings are arranged alongside theelongate slot; and (b) a pair of elongate ribs disposed on the deck,wherein the elongate ribs extend longitudinally along opposed lateralsides of the elongate slot.

Example 12

The staple cartridge of any of the preceding Examples, wherein thecartridge body extends linearly along a longitudinal axis.

Example 13

A surgical stapler comprising: (a) a first stapler half having a firstdistal portion that supports an anvil; (b) a second stapler half havinga second distal portion; and (c) the staple cartridge of claim 1,wherein the second distal portion is configured to receive the staplecartridge, wherein the first and second stapler halves are configured toreleasably couple together to clamp tissue between the anvil and thestaple cartridge.

Example 14

The surgical stapler of Example 13, wherein each of the staples includesa crown from which the pair of legs extends, wherein the anvil isconfigured to form the legs of the staples such that leg tips of eachstaple are laterally offset from one another and the crown on opposedsides of the crown when the legs are formed.

Example 15

The surgical stapler of any of Examples 13 through 14, wherein thesecond stapler half includes: (i) a firing assembly, wherein the firingassembly is selectively actuatable distally to actuate the stapledrivers to drive the staples from the staple openings, through tissue,and against the anvil, wherein an underside of the firing assemblyincludes a recess, and (ii) a resilient member, wherein when the staplecartridge is absent from the second distal portion, the resilient memberis configured to bias the firing assembly into a lockout state andthereby inhibit distal actuation thereof, wherein when the staplecartridge is initially seated within the second elongate member, thefiring assembly is configured to assume a firing state in which thefiring assembly is translatable distally over the resilient member in adeflected state such that a portion of the resilient member is receivedwithin the recess of the firing assembly.

Example 16

The surgical stapler of Example 15, wherein the second stapler halffurther includes a guide member having a channel, wherein the resilientmember extends longitudinally through the channel, wherein the resilientmember is configured to resiliently deflect within the channel when thefiring assembly is advanced distally.

Example 17

A staple cartridge configured for use with a surgical stapler,comprising: (a) a cartridge body; (b) a deck defined by the cartridgebody, wherein the deck is configured to compress tissue against an anvilof the surgical stapler; (c) a plurality of staple openings formed inthe deck; (d) a plurality of staples disposed within the stapleopenings, wherein each of the staples includes a first leg and a secondleg; and (e) a plurality of staple drivers disposed within the stapleopenings, wherein the staple drivers are actuatable to drive the staplesthrough tissue and against the anvil to form the legs, wherein each ofthe staple drivers includes: (i) a first lateral side having a firstchamfered surface, and (ii) a second lateral side having a secondchamfered surface, wherein the first chamfered surface is configured toreceive the first leg of a respective staple in a confrontingarrangement and the second chamfered surface is configured to receivethe second leg of the respective staple in a confronting arrangementwhen the first and second legs are formed against the anvil.

Example 18

The staple cartridge of Example 17, wherein an upper end of each of thestaple drivers is configured to support the respective staple, whereinthe first and second chamfered surfaces extend to the upper end.

Example 19

A surgical stapler comprising: (a) a first elongate member having adistal portion that supports an anvil; (b) a second elongate memberhaving a distal portion configured to receive a staple cartridge,wherein the first and second elongate members are configured toreleasably couple together to clamp tissue between the anvil and thestaple cartridge; (c) a guide member secured to the second elongatemember; (d) a resilient member secured to the guide member; and (e) afiring assembly slidably coupled with the second elongate member,wherein an underside of the firing assembly includes a recess, whereinthe guide member is configured to guide translation of a portion of thefiring assembly relative to the second elongate member, wherein when astaple cartridge is absent from the second elongate member, theresilient member is configured to bias the firing assembly into alockout state and thereby inhibit distal actuation thereof, wherein whenan unspent staple cartridge is seated within the second elongate member,the firing assembly is configured to assume a firing state in which thefiring assembly is translatable distally over the resilient member in adeflected state such that a proximal end of the resilient member isreceived within the recess of the firing assembly.

Example 20

The surgical stapler of Example 19, wherein the resilient member extendslongitudinally through the guide member, wherein the resilient member isconfigured to resiliently deflect within the guide member when thefiring assembly is advanced distally.

VI. Miscellaneous

It should be understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Theabove-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims.

Further, any one or more of the teachings, expressions, embodiments,examples, etc. described herein may be combined with any one or more ofthe teachings, expressions, embodiments, examples, etc. described inU.S. application Ser. No. 15/889,363, entitled “Release Mechanism forLinear Surgical Stapler,” filed on Feb. 6, 2018; U.S. application Ser.No. 15/889,370, entitled “Lockout Assembly for Linear Surgical Stapler,”filed on Feb. 6, 2018; U.S. application Ser. No. 15/889,374, entitled“Features to Align and Close Linear Surgical Stapler”,” filed on Feb. 6,2018; U.S. application Ser. No. 15/889,376, entitled “ReleasableCoupling Features for Proximal Portions of Linear Surgical Stapler,”filed on Feb. 6, 2018; U.S. application Ser. No. 15/889,388, entitled“Firing Lever Assembly for Linear Surgical Stapler,” filed on Feb. 6,2018; U.S. application Ser. No. 15/889,390, entitled “Clamping Mechanismfor Linear Surgical Stapler,” filed on Feb. 6, 2018; U.S. patentapplication Ser. No. 16/102,164, entitled “Firing System for LinearSurgical Stapler,” filed on Aug. 13, 2018; U.S. patent application Ser.No. 16/102,170, entitled “Clamping Assembly for Linear SurgicalStapler,” filed on Aug. 13, 2018; U.S. application Ser. No. 16/157,599,entitled “Anvil Assembly for Linear Surgical Stapler,” filed on Oct. 11,2018; U.S. application Ser. No. 16/157,605, entitled “Closure Assemblyfor Linear Surgical Stapler,” filed on Oct. 11, 2018; and/or U.S. patentapplication Ser. No. 16/165,587, entitled “Decoupling Mechanism forLinear Surgical Stapler,” filed on Oct. 19, 2018. The disclosure of eachof these applications is incorporated by reference herein.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Versions of the devices described above may have application inconventional medical treatments and procedures conducted by a medicalprofessional, as well as application in robotic-assisted medicaltreatments and procedures. By way of example only, various teachingsherein may be readily incorporated into a robotic surgical system suchas the DAVINCI™ system by Intuitive Surgical, Inc., of Sunnyvale, Calif.

Versions of the devices described above may be designed to be disposedof after a single use, or they can be designed to be used multipletimes. Versions may, in either or both cases, be reconditioned for reuseafter at least one use. Reconditioning may include any combination ofthe steps of disassembly of the device, followed by cleaning orreplacement of particular pieces, and subsequent reassembly. Inparticular, some versions of the device may be disassembled, and anynumber of the particular pieces or parts of the device may beselectively replaced or removed in any combination. Upon cleaning and/orreplacement of particular parts, some versions of the device may bereassembled for subsequent use either at a reconditioning facility, orby a user immediately prior to a procedure. Those skilled in the artwill appreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, versions described herein may be sterilizedbefore and/or after a procedure. In one sterilization technique, thedevice is placed in a closed and sealed container, such as a plastic orTYVEK bag. The container and device may then be placed in a field ofradiation that can penetrate the container, such as gamma radiation,x-rays, or high-energy electrons. The radiation may kill bacteria on thedevice and in the container. The sterilized device may then be stored inthe sterile container for later use. A device may also be sterilizedusing any other technique known in the art, including but not limited tobeta or gamma radiation, ethylene oxide, or steam.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

I/We claim:
 1. A staple cartridge configured for use with a surgicalstapler, comprising: (a) a cartridge body; (b) a deck defined by thecartridge body, wherein the deck is configured to compress tissueagainst an anvil of the surgical stapler; (c) a plurality of stapleopenings formed in the deck; (d) a plurality of staples disposed withinthe staple openings, wherein each of the staples includes a pair oflegs; and (e) a plurality of staple drivers disposed within the stapleopenings, wherein the staple drivers are actuatable to drive the staplesthrough tissue and against the anvil to form the legs, wherein each ofthe staple drivers includes: (i) a driver body, (ii) a first pocketdisposed on a first lateral side of the driver body, and (iii) a secondpocket disposed on a second lateral side of the driver body, wherein thefirst and second pockets are configured to receive the legs of therespective staple when the legs are formed against the anvil.
 2. Thestaple cartridge of claim 1, wherein the first pocket and the secondpocket open to an upper end of the driver body.
 3. The staple cartridgeof claim 1, wherein each of the staple drivers further includes a firstboss disposed on the first lateral side of the driver body and a secondboss disposed on the second lateral side of the driver body, wherein thefirst boss defines a sidewall of the first pocket, wherein the secondboss defines a sidewall of the second pocket.
 4. The staple cartridge ofclaim 1, wherein the first pocket is defined by a first chamferedsurface on the first lateral side of the driver body, wherein the secondpocket is defined by a second chamfered surface on the second lateralside of the body.
 5. The staple cartridge of claim 4, wherein upperportions of the first and second chamfered surfaces are angled towardone another.
 6. The staple cartridge of claim 1, further comprising aplurality of stand-off members disposed on the deck, wherein thestand-off members project away from the deck and are configured toengage tissue.
 7. The staple cartridge of claim 6, wherein each of atleast some of the stand-off members includes an end portion that wrapsaround a portion of an adjacent staple opening.
 8. The staple cartridgeof claim 7, wherein the end portion includes a rounded end surfaceconfigured to confront a respective one of the staple drivers when thestaple driver is actuated.
 9. The staple cartridge of claim 6, whereinthe stand-off members include a ramp feature disposed at a distal end ofthe deck.
 10. The staple cartridge of claim 9, further comprising a postdisposed at a distal end of the deck, wherein the ramp feature isarranged distally of and in longitudinal alignment with the post along alongitudinal axis of the staple cartridge.
 11. The staple cartridge ofclaim 1, further comprising: (a) an elongate slot formed in the deck,wherein the elongate slot is configured to slidably receive a cuttingmember therethrough, wherein the staple openings are arranged alongsidethe elongate slot; and (b) a pair of elongate ribs disposed on the deck,wherein the elongate ribs extend longitudinally along opposed lateralsides of the elongate slot.
 12. The staple cartridge of claim 1, whereinthe cartridge body extends linearly along a longitudinal axis.
 13. Asurgical stapler comprising: (a) a first stapler half having a firstdistal portion that supports an anvil; (b) a second stapler half havinga second distal portion; and (c) the staple cartridge of claim 1,wherein the second distal portion is configured to receive the staplecartridge, wherein the first and second stapler halves are configured toreleasably couple together to clamp tissue between the anvil and thestaple cartridge.
 14. The surgical stapler of claim 13, wherein each ofthe staples includes a crown from which the pair of legs extends,wherein the anvil is configured to form the legs of the staples suchthat leg tips of each staple are laterally offset from one another andthe crown on opposed sides of the crown when the legs are formed. 15.The surgical stapler of claim 13, wherein the second stapler halfincludes: (i) a firing assembly, wherein the firing assembly isselectively actuatable distally to actuate the staple drivers to drivethe staples from the staple openings, through tissue, and against theanvil, wherein an underside of the firing assembly includes a recess,and (ii) a resilient member, wherein when the staple cartridge is absentfrom the second distal portion, the resilient member is configured tobias the firing assembly into a lockout state and thereby inhibit distalactuation thereof, wherein when the staple cartridge is initially seatedwithin the second elongate member, the firing assembly is configured toassume a firing state in which the firing assembly is translatabledistally over the resilient member in a deflected state such that aportion of the resilient member is received within the recess of thefiring assembly.
 16. The surgical stapler of claim 15, wherein thesecond stapler half further includes a guide member having a channel,wherein the resilient member extends longitudinally through the channel,wherein the resilient member is configured to resiliently deflect withinthe channel when the firing assembly is advanced distally.
 17. A staplecartridge configured for use with a surgical stapler, comprising: (a) acartridge body; (b) a deck defined by the cartridge body, wherein thedeck is configured to compress tissue against an anvil of the surgicalstapler; (c) a plurality of staple openings formed in the deck; (d) aplurality of staples disposed within the staple openings, wherein eachof the staples includes a first leg and a second leg; and (e) aplurality of staple drivers disposed within the staple openings, whereinthe staple drivers are actuatable to drive the staples through tissueand against the anvil to form the legs, wherein each of the stapledrivers includes: (i) a first lateral side having a first chamferedsurface, and (ii) a second lateral side having a second chamferedsurface, wherein the first chamfered surface is configured to receivethe first leg of a respective staple in a confronting arrangement andthe second chamfered surface is configured to receive the second leg ofthe respective staple in a confronting arrangement when the first andsecond legs are formed against the anvil.
 18. The staple cartridge ofclaim 17, wherein an upper end of each of the staple drivers isconfigured to support the respective staple, wherein the first andsecond chamfered surfaces extend to the upper end.
 19. A surgicalstapler comprising: (a) a first elongate member having a distal portionthat supports an anvil; (b) a second elongate member having a distalportion configured to receive a staple cartridge, wherein the first andsecond elongate members are configured to releasably couple together toclamp tissue between the anvil and the staple cartridge; (c) a guidemember secured to the second elongate member; (d) a resilient membersecured to the guide member; and (e) a firing assembly slidably coupledwith the second elongate member, wherein an underside of the firingassembly includes a recess, wherein the guide member is configured toguide translation of a portion of the firing assembly relative to thesecond elongate member, wherein when a staple cartridge is absent fromthe second elongate member, the resilient member is configured to biasthe firing assembly into a lockout state and thereby inhibit distalactuation thereof, wherein when an unspent staple cartridge is seatedwithin the second elongate member, the firing assembly is configured toassume a firing state in which the firing assembly is translatabledistally over the resilient member in a deflected state such that aproximal end of the resilient member is received within the recess ofthe firing assembly.
 20. The surgical stapler of claim 19, wherein theresilient member extends longitudinally through the guide member,wherein the resilient member is configured to resiliently deflect withinthe guide member when the firing assembly is advanced distally.